The Source Key
by celesteavonne
Summary: Rose & the Doctor slide sideways into Sunnydale right as the First is sinking its teeth into the Scooby gang. Can the Doctor & the Slayer figure out what the Source is in time to stop an alien race from noshing on tasty humans? And where does Dawn fit in?


**Doctor Who Season Three, Tenth Doctor; Rose Tyler, companion.**

**Set after Episode 20 (_The Age of Steel_)**

**Buffy Season Seven, Buffy Summers, Slayer and the Scoobies**

**Set between Episodes 10 and 11 (_Showtime _and _Potential_)**

**Rating: PG**

**Pairings: Buffy/Spike; Rose and the 10th Doctor**

Disclaimer: I own nothing; just playing with other people's toys. Credit for _Buffy_ goes to Joss Whedon. Credit for _Doctor Who_ and _Torchwood_ goes to Russell T. Davis. "Begun by blood, by blood undone," is a quote from _Pirates of the Caribbean_. The Vriskian Fellowkind, Frak, Frell, and Senator Frawlis are mine, though.

* * *

><p>The TARDIS juddered to a halt, slamming the Doctor and Rose to the floor. Smoke hissed from the controls as crawled toward each other through the sudden, inky darkness of the bridge.<p>

"What's happened?" Rose asked.

"We've stopped," he said.

"I sorta worked that out," she said. They met at the central walkway as the emergency generator came online. Amber glow painted their features in pale gold and shadow, but even in the wan light, she could make out the curve of his smile.

"That's funny. I didn't see an excursion in our itinerary. You?"

Rose shook her head.

He laced his fingers with hers and together they struggled to their knees. "Must have a word with our cruise director…"

"Doctor—" Rose knew him well enough to know when he was trying to make light of something astronomically heavy.

"It was a rough drop," he said.

"One of the worst."

"Only one rougher, which means…"

"We've fallen out of the time vortex."

"Yeah—"

Just then, the door to the TARDIS burst open and in stumbled a breathless and bedraggled teenage girl. The girl – wide-eyed with shock as she took in the unexpected enormity of her surroundings – staggered to a halt. Her frightened gaze settled on the Doctor and Rose.

"Oh," she whimpered. "Hi?"

The Doctor arched an eyebrow and said, "Well. You're… _new_."

Rupert Giles awoke to a startling sound, like a thunderclap followed by a severe gale of wind. He rolled from bed, went to the window, and twitched back the curtains, only to peer out at a starlit sky.

Still, his heart hammered in his chest. He knew that sound. He i_knew_/i it. But how?

Giles went downstairs, past a room full of furniture still dressed as ghosts. He wondered dimly whether he should bother removing the sheets he'd draped over them when he last left in May to take Willow to Westbury. He had been so careful with his leather divan and all of those priceless books. All his adult life, so careful, but now he wondered if it mattered at all.

_Well, now_, he thought. _Isn't that cheery?_

He took down a mug and a teabag from the cupboard, but upon consideration, he went instead for the bottle of Glenfiddich stowed atop the refrigerator. He poured two fingers into a glass and downed it in a shot.

Giles set the tumbler beside his journal, which bristled now with dog-eared scraps of lists and maps and boarding passes. The latest poked from the top, it's red and blue airline logo obscured by the closed book. At the moment, he couldn't recall where in the world he'd be traveling. Calcutta, perhaps? Beijing?

Didn't matter. Nothing mattered but the job. He would gather the girls – the Potentials – and hope that they would be enough.

Giles picked up the bottle of Scotch. He tipped it toward his glass but paused before pouring. The thought of the dream nettled him. He tried to recall that sound and wondered, with all the chaos around them, why it would disturb him so.

He recapped the bottle, put it away. He entertained the idea of returning to bed, but he doubted he could sleep.

As he went upstairs to change, he felt that nagging tug again: That sound. That wonderful, terrible sound, like that of an oncoming storm.

* * *

><p>Spike let the halberd drop to the floor with a clatter, earning him cross looks from Willow and Kennedy and a harsh "Shhh!" from Xander.<p>

Buffy knew it was an accident, but also knew that the last thing they needed was a swarm of worried teenage girls listening in to how the latest entry in the Sunnydale Bestiary kicked their collective asses. Rather than risk a confrontation of angry stage whispers, Buffy opted to get right to work.

"Guys, any ideas about what the hell those things were?"

"We can safely rule out human," Kennedy said.

"We can safely rule out Bringer," Anya added. "And vampire."

"But the masks…" Willow said, trailing off as if following the thought down another path.

"And the laser things," Xander said. "Let's not forget those."

"Whatever they are, they wanted to appear human," Spike said. "Least at a distance."

Spike wiped blood from a cut on his already bruised forehead. Buffy took in the condition of his knuckles, which were so split and bloody it looked as though he'd gone five rounds with an industrial strength cheese grater. He wasn't ready to return to the fight, but he had insisted.

Turns out, it was good he did. There were so many of them, and all of them as strong as the average vampire with the added bonus of some kind of plasma weapon, and the Scooby gang i_so/i_ did not need any of this right now.

Spike caught her staring at him and narrowed his eyes. He shook his head, barely perceptible, and she looked away.

"Oh, wait!" Willow said. "I almost forgot."

She took out a rumpled sheet of lined notebook paper, smudged with dirt and flecked with blood. On it, in ballpoint pen, was a complicated series of overlapping circles and swirls and lines, with a scattering of points and Xs across the field of the page. At the bottom was a line of random letters and numbers: RA 17 h 05 m 37.952 dec-10° 08′ 34.58″

"I found this. We," she glanced at Kennedy and smiled. "We found this at the site, just before the screaming and the running. Maybe it's important?"

Buffy lifted the scrap of paper. "Blood," she said.

"Always blood," Spike said. "But what's with the scribble? Bit complex for the average Hellmouth High graduate."

"Doesn't look demonic," Anya said.

"How you figure?" Xander asked.

Anya took the paper from Buffy and spread it flat. "These," she said, gesturing to the numbers. "They look like coordinates on a map. A key of sorts. And these," she gestured to the lines, "Appear to be some kind of casting. You got your rising planets, setting suns. I'd say this is high level Astrology. Somebody's getting Wicca with it."

Willow examined the page. She turned it in her hands and said, with a measure of doubt, "This doesn't look like any reading I've ever seen."

"Of course it doesn't," Anya snapped. She snatched the page and placed it back on the table. "And it's not a conjuration."

"So what is it?" Buffy asked. "More importantly, what are they? Those demon-y mask creatures."

Shrugs all around. Xander said, "Maybe Giles would know?"

"We can't ask him," Buffy answered. "He's leaving for China in the morning, and he's already way wigged. Let him rest. We'll handle this one on our own."

"Very well," Willow said, taking the sheet of paper. "To the Net." She and Kennedy headed to the dining room.

"Very well, to the books," Anya said. She tucked her arm in Xander's and hauled him into the living room, where they had to nudge a sleeping Andrew out of the recliner so they'd have enough space to even open a book.

This left Buffy standing across from Spike, and for a long moment, neither of them seemed to know what to say.

"Relax, Slayer," he said at last. "It's likely Demon of the Week. With the First setting up shop, it's like a neon sign: Open for Business. I'm surprised we haven't seen more."

"That's what I'm afraid of," she whispered. "We're already at the fill line for bad things. We have a house full of scared girls with more on the way and a bevy of monsters just waiting to cut their teeth on the bones of Potentials. Haven't we already hit our quota? Can't we have something work in our favor, for once?"

Spike bent to pick up his halberd. He winced as he straightened, but made an effort to hide it. "Something will," he said. "Something always does."

Buffy nodded, but had to marvel at his faith. He gave her a smirk and disappeared around the corner, heading for his basement bed. She wished she could share in his belief that they would all see this one through. But she didn't. Not this time.

* * *

><p>The Doctor swept the sonic screwdriver in front of the girl's eyes as she spoke, her words rushed and tangled, about how she came to be aboard the TARDIS. Rose had pulled out a first aid locker and was busy winding a length of gauze around a nasty scrape on the girl's left forearm.<p>

"…at first I thought I'd climb out the storm drain," she said. "Because maybe they couldn't leave the sewer or maybe they'd just lose me in the street and I'd get home, but they were so fast and they had some kind of blaster gun thing."

Rose and the Doctor exchanged a look. The Doctor adjusted a setting on the sonic screwdriver and continued to scan.

"Then, out of nowhere, I saw this blue box with lights on top, and I thought, 'hey, I can hide in there'. But then I opened the door and… This," she said, with a sweep of her free hand.

"Ye-es," the Doctor said. "That's just it. No one's meant to get in here."

The girl shot a worried look at Rose. "I-I'm so sorry. I didn't—"

"No, it's all right," he said. "It's merely…curious. And you say you were chased?"

The girl nodded.

"Tell us about that."

The girl hesitated a moment. She said, "At first I thought they were…something else."

"Something… _else_?" the Doctor asked.

"Well, they wore masks," the girl said. "Human masks. Like, faces of famous people."

"Oh, yeah," Rose said. "Seen it before in bank heist movies. Dead presidents 'n the like."

"Only their skin was scaly, kind of – chitinous—"

The Doctor perked up but said nothing.

The girl went on. "Like they were made of metal, and there was this smell." The girl's nose wrinkled at the memory. "Like burning oil."

The Doctor adjusted the sonic screwdriver again and ran a sweep over the top of the girl's head.

"What is that?" the girl asked.

When the Doctor didn't reply, Rose said, "It's a sonic screwdriver."

"Does it, like, open sonic fuse boxes?"

Rose laughed. "Funny. I like this one."

"Yes," the Doctor said, seemingly absorbed by the readings from his scan. "Who wouldn't? She's adorable."

The girl flounced and rolled her eyes. "If I was a puppy that'd be swell. But I'm not. I'm just… ordinary."

The Doctor sat back on his heels and switched off the screwdriver. He scratched behind his ear. "No, I wouldn't say that."

The tiniest flicker of alarm played across the girl's face. She looked again at Rose, who responded with a questioning smile, and then at the Doctor, who eyed her with distinct interest.

"So what is this place?" the girl asked.

"It's a ship," the Doctor said.

"A spaceship," Rose added.

The girl's brow furrowed. "And you're, what, aliens?"

"Well—" the Doctor said.

"I'm not," Rose said. "I'm human, same as you."

"But he's _not_?" The girl stared into the Doctor's eyes a long, silent moment. Then she said, "Don't you have a shield on this thing? Like a force field, or – oh! Protection spell?"

The Doctor shrugged. "It's triple dead-locked. Besides most people ignore it, walk on by, but you…"

"You just burst right in," Rose said.

"What'd you say your name is?" the Doctor asked.

"I, um…" the girl got to her feet and backed away. "Really, thanks, but I should probably get going."

"With those fings out there? Don't be mad," Rose said. "We'll go with you. Won't we, Doctor?"

The girl's eyes widened to near panic as she took another retreating step. "You're the Doctor? But you can't be. You're—"

The Doctor got to his feet, his hands raised. "Now, now," he said. "I'm fair certain we've never met, but I can see by your eyes you've met another of the same name?"

The girl nodded. She looked as though she might bolt at any second.

Then Rose stood and said, "Listen. Please. Don't go out there. We can help. Now, I'm Rose, and this man, the Doctor, you can trust him, all right? I promise."

The girl clenched and unclenched her fists. The Doctor could see her weighing out her options – the beasts in the sewer versus him and Rose. She definitely had something to hide and seemed well-equipped at hiding it. Many questions whirled in his mind, not the least of which was how they came to crash-land here right in time for this strange girl to tumble into their path. Even if she chose to run, the Doctor knew that he and Rose would pursue her. She was the key at the center of the mystery.

Finally, the girl shook her head. "Fine," she said.

"There we are," the Doctor said, pulling Rose into a side-hug.

"My names is Dawn," the girl said. "Dawn Summers."

* * *

><p>Giles whipped the sheet from the sealed oak trunk at the end of his bed. With a skeleton key he always kept on his keyring, he opened the lock and shoved back the lid. A waft of age and dust struck him – moldering trinkets and mildewing papers lain to rest over four decades.<p>

He hoped never to open this trunk again, but he had always known he would need to, one day.

He dropped to his knees and waded through crumbling texts and tarnished relics until he found a teakwood cigarette case in the bottom corner. He popped the back cover off to expose a secret compartment inside. There, he found a thin square wafer of luminous green glass etched with intricate geometric patterns, and a white card with an international telephone number scritched in black ink.

Giles sat back in the small space between the trunk and the wall and ran a trembling hand through his hair.

When he felt his breathing had settled enough to speak, he pulled his cell phone from his pocket and dialed.

A series of clicks and bleeps followed, and then someone answered.

"I don't know how it's possible," Giles said. "But he's here. The Doctor has returned."

* * *

><p>"Something. Is definitely. Wrong." The Doctor whispered the words into Rose's ear as they followed Dawn through the silent, sleeping streets of Sunnydale, California.<p>

"Yeah, I feel it," Rose whispered back. "Kind of like biting down on tin. What is it?"

"Whatever it is, it's gone on long enough they've adjusted. They don't feel it."

Rose sucked air over her teeth and shuddered. "How can they not?

The Doctor shrugged. "Humans grow accustomed to all manner of things. You adapt. It's what you do."

Dawn walked several paces ahead, her whole body rigid and alert, as if something might leap out at them at any turn. Still, Rose could tell that the girl was trying very hard to appear brave.

"What about her?" Rose asked. "How'd she just dash into the TARDIS like that? And right after we crashed. It's all a bit odd, innit?"

"Yes. Very," he said. "The readings I got off her. They were incongruous."

"How do you mean?"

"She appears to be, what, seventeen?"

"At a guess."

"Well, first reading said a million plus years; second said two and a quarter."

"That's impossible," Rose said, a little too loud. Dawn cringed and shushed them.

"Sorry," the Doctor said.

After they'd walked a while in silence, Rose whispered, "She's clearly not a toddler."

He wibbled his head. "Neither is she Boe kind, and yet…"

"So what is she?"

"That," the Doctor said, "is what we're meant to find out."

Dawn crouched behind a hedgerow and motioned for them to join her. They peaked through the leaves to see a modest house across the street, with a wide porch and lovely trees. Only, Rose couldn't help but notice that the front windows were boarded over and a glitter of glass sparkled across the front walk.

"We made it," Dawn said. "Wreck sweet wreck."

"I fink it's lovely," Rose said.

"You might not think so if my sister's still awake. She'll skin me alive once she knows I've been out." Dawn's brow clouded. "She won't really skin me alive. That's… someone else. It's not important. Ready?"

"Yeeeah," the Doctor said doubtfully.

Dawn leapt up and darted across the street with the Doctor and Rose close behind her.

* * *

><p>Senator Frawlis paced along the concrete gangplank between the twisted hull of his damaged ship and the makeshift receptor antenna his crew had created from scavenged neon tubing, a microwave oven, a TV aerial, several hundred feet of cable, the cannibalized communications deck of the bridge, and a pair of Slinkies.<p>

His head minions, Frell and Frak, cowered in the sludge below. Frell's mask had slipped to the side, revealing one glowing blue eye and a strip of his molded metal face. If Frawlis had been in a better mood, he might have laughed at the comedic appearance of his comrade's motley double face – the sneering monster alongside the grinning jester. The robot and the clown.

But now was not the time.

"Report," Frawlis snapped, swirling his cape as he turned on them.

"M-many complications, Senator," Frell said. "First, there were others in pursuit of the Source—"

"—Men with jigsaw eyes," Frak put in.

"Yes, with sharp, sharp knives, Resplendent One, and then," Frell nudged his mask.

"And then another Source appeared," Frak said.

Frawlis halted mid-pace. "A _second_ Source?"

"Yes, Oh Lenient and Just," Frell said.

"S-so we divided our ranks," Frak continued. "Group Senchay targeted the first Source."

"While Group Dorlay targeted the second."

Both Frell and Frak fell to abjectly wringing their talons.

Senator Frawlis stamped the ground with his mighty metal footpad, which rang in the cavern like the tolling of a bell. Both minions trembled. "Then what happened?" Frawlis boomed.

"W-well," Frak said. "Group Dorlay encountered fighters, sir."

"Fighters?" Frawlis said.

"Yes, Your Benevolence. We believe it was the Slayer," Frak said.

"And friends," Frell added.

"Losses?" Frawlis asked.

"F-four," Frell said.

Frawlis nodded. "Acceptable. Then what?"

"Group Dorlay retreated but continued to track the second signal," Frak said.

"Meanwhile, Group Senchay had a lock on the Source and were closing in," Frell said. "But then, something… odd."

"Elaborate," Frawlis demanded.

"The signals, they…" Frak said.

"…Converged, Good Sir," Frell said.

"And then both – _poof _– disappeared," Frak finished.

Frawlis pressed his talons flat. He narrowed his eye slits at the minions. "Elaborate," he said, his voice modulating in a deep and deadly measure.

"That's just it, Good Sir. Kind Sir. Most Magnanimously Patient Sir. We have no idea," Frak said. "Sir."

In times past, such incompetence would be punished with a laser bolt to the brainpan, and how Frawlis wished to unholster his blaster and incinerate the latex smile right off Frak's face…

But with four lost to the Slayer and the additional twelve who died in the crash, they were critically close to having too few to crew the ship once they secured the power to get it started. They needed the Source. They needed time. More than that, they needed each other. Oh, how loathsome they had become.

A tiny ping resonated in Frawlis' neck coil, and he growled.

"Food," Frawlis hissed.

Frak and Frell sprung to their foot clamps. "Yes, Sir, right away, Sir," they shouted. Together they clambered over one another, up the service ladder, to the hatch that let them into the sewers above.

"Mind your masks!" Frawlis called out, and saw Frell pull his back in place before he disappeared into the tunnel.

Down the corridor behind him, behind the wreck of the ship, Frawlis heard the scraping clangor of the rest of them – his crew, his _family_ – returning from the fray. No doubt they would be hungry as well. Luckily, this town had plenty of tasty humankind to last them until they found the Source. In fact, he thought they ought to consider packing a few extra for the return trip. Maybe some of the smaller ones, as snacks.

_Oh, I am benevolent, indeed_, Frawlis thought. _My title is well-earned. See how I care for my Fellowkind, through all of our suffering and strife_. He went forth into the tunnel to issue the order to his comrades: go out and gather as many as possible. After all, it wouldn't do to travel on an empty stomach.

* * *

><p>"We have to be very quiet," Dawn told them as they entered the foyer of the Summers house. The reason became clear right away. A dozen or so young girls slept on pallets of mismatched sheets, blankets, pillows, and cushions scattered across the floor of the living room. The house reeked of burned pasta, scorched coffee, and sweat – in short, the scent of fear.<p>

"Massive slumber party?" the Doctor ventured.

"You could say that," Dawn said. "There are more upstairs and more on the way."

"Who are they?" Rose asked. "Why are they here? What's happening?"

"Dawnie?" A young red-headed woman and dark-haired friend stared at them from the archway.

"It's okay," Dawn rushed to explain. "They're nice."

The dark-haired girl circled them, hands on her hips. "Another one?" she asked, gesturing to Rose, and then jabbing a finger at the Doctor, "You her Watcher?"

"That's right," the Doctor said. "That's what I am. I'm her Watcher."

Rose shot him a quizzical look. He responded with a head tilt that meant he'd explain everything later.

"T-that's right," Dawn said. "Willow, Kennedy: This is Rose, another Potential, and her Watcher. He's the Doctor."

"The Doctor?" Willow muttered. "Doctor Who?"

"Just the Doctor," Rose explained.

"Well aren't you lucky?" Kennedy bit out. "Not only do you arrive without becoming a Bringer kebab, but you get to keep your Watcher. Good on you."

Rose bristled at the other girl's tone. "Excuse me, what exactly is a Bringer?"

Kennedy rolled her eyes and turned to Willow. "You believe this newbie? And guess what else. They're British. How we gonna fight the First with the God Save the Queen brigade? Probably gotta have tea and crumpets before even lifting a stake—"

"Hey!" the Doctor and Rose said together.

But Kennedy bowed up to Rose, nose to nose, and said, "We need fighters."

"Oi, back off!" Rose shoved her hard as she could, but the girl barely even moved.

The Doctor and Willow intervened, but not before they'd roused half the house. A semi-circle of girls in jim-jams crowded into the arch between the entry hall and the living room. Some of them sported fading bruises and scrapes, and all of them appeared worn to the point of despair. Beyond the crowd of girls stood a pair of men and a woman. The younger of the men had tell-tale bite marks on his neck.

"Ah," the Doctor said. "Fighters. Vampires. That would make you…" he turned to address the blonde figure that had been steadily, stealthily descending the stairs, "The Slayer."

* * *

><p>This was ludicrous. Certifiably. Without a doubt one of the dumbest things Rupert Giles had ever done.<p>

Yet here he was, alone, in a sewer tunnel north of downtown with a torch in one hand, a palm-sized square of glass in the other, and the rather thin assurance from one junior time agent that the artifact would work if he managed to get within twenty meters of the object in question.

Junior time agent had not sounded remotely convinced that Giles had heard what he thought he heard, and really, Giles had to admit that not even he felt entirely convinced now that he was skulking through stinking, sweltering corridors under Sunnydale in search of – what, exactly? – a sound? From a dream?

Moreover, he had a flight to China in five hours' time. He had a duty to his Slayer and what remained of the Watcher's Council, to gather the Potentials found by the Coven and see them delivered safely here.

Where they would find certain and unspeakable dangers in the face of the Hellmouth.

But this – he held the small wafer of glass up to the light of the torch – this had the potential to change everything. He could use it to seal up the Hellmouth forever and no more girls would have to die. It could save the whole world – the whole universe.

Giles heard a scuffling in the dark. He switched off his torch and pressed against the wall, hoping that whatever it was, it wouldn't be able to smell his blood or hear his pounding heart.

A full minute he waited, holding his breath, listening to the endless trickling of water. He was preparing to move again when he saw a spangle of light splash across the tunnel wall nearly fifty paces back the way he had come. Then he heard the scraping of footfalls and murmuring voices. Giles dived across the hallway into a triangular service niche where he hoped he could hide until they passed.

And if they saw him, he could bash in at least one of their heads with his torch. _Idiot_, he thought. _Sunnydale, at night, in a sewer tunnel, and I've neglected to grab a weapon?_

The sound of clattering feet drew closer. Two creatures, Giles guessed, possibly _dragging_ a third? As they neared, he could make out fragments of their conversation.

"—said it would come quietly—"

"—didn't know it had a striking weapon—"

"—dented my receptor—"

"—I know, I know, I'm sorry."

They halted a moment and a beam of light spilled across the entry to Giles' hiding spot. He squeezed tighter against the wall.

"Looks all right," the one said.

"Does it?" The second whimpered.

"Tore your face a bit, but the dome's fine. Once we get up-top, Orxalyx'll pop that right out, good as new."

The second creature sniffled. "I miss up-top. Been so long."

"Chin up, Frell," the first said. "Once we find the Source, it's a matter of zip-bang-boom, to the moon."

Giles then heard a gurgling sort of moan.

"Oi, it's waking. Quick, lightburst it. Senator Frawlis hates when they're wake," the first voice said.

"Ach," the second answered, sounding annoyed. "'E's just being finicky. They taste the same either way."

"That's our master," the first said.

A burst of blue-white light flashed the tunnel, followed by a crackling sound and the sharp scent of ozone.

"All better," the second voice soothed, and they began their shuffling walk again.

In a few moments, Giles watched them rattle past – two scaly creatures slightly smaller than a grown man, with articulated dorsal fins and talons, dragging between them the limp body of a balding man in a bathrobe. Though he couldn't be sure because of the jostling light and the quickness of their passage, Giles was almost certain the creatures wore masks.

Once they'd passed, Giles waited a hundred count before sliding back into the corridor. His feet ached from the damp and his head throbbed from exhaustion, but he now had even more unanswered questions.

Namely, could it be that the Source these creatures mentioned was the same object he sought?

If that was the case, Giles knew he had to find it first.

He had walked another fifteen minutes or so when he felt the first flutter from the glass wafer. It took him by so much surprise he dropped his torch to the tunnel floor and the light guttered, leaving him in total darkness.

Except for the faint glow of the disc.

Giles cupped the wafer in his hands. i_Yes! He hadn't imagined it._ /i The wafer pulsed with a pale green light.

He collected his torch and got to his feet. He walked a few steps in the same direction he'd been traveling and held up the wafer once more. As he hoped, the gentle pulse had intensified. A minute difference, but it showed that he was on the right path.

He continued like this for the better part of an hour, fumbling through the dark with only a pulsating wafer of light to guide him. For a long while, it radiated at the same rate and intensity – so much so that Giles began to doubt if he'd been right at all – but then he rounded a junction and the pulse spiked to brilliant gold, so bright it left him momentarily blind.

Once his vision adjusted, Giles felt his way forward over the slick and uneven paving stones, blind to everything but the light of the wafer. Between flares, his eyes burned with the afterimage, but he went on, step after careful step, until he felt his knuckles brush against something decidedly wooden: A door.

Giles pocketed his torch and clapped both hands over the wafer. The light dimmed but still seeped between his fingers, giving off enough glow for him to read by. He smiled at the trickle of hope in his heart. He recognized it, the blue police box from his adolescence in London. But it was so much more than that. So much more.

Giles reached out, and with the wafer still clutched in his hand, he tried the knob.

It held fast. Giles pointed the wafer at the keyhole. The wavering pulse continued, but nothing happened. He pressed it flat against the door. Still, nothing. The door was locked. If he couldn't get inside, he couldn't use the wafer, and if he couldn't use the wafer, he couldn't close the Hellmouth.

Frustrated, Giles sat down on the ground and pressed his back against the door. _There must be something I'm missing_, he thought. _Something vital, but probably so simple…_

Despair welled up in his throat, threatening to team up with his aching joints and crippling fatigue to overwhelm him. But he couldn't let it. Not now. Not when he was so close.

After all, he'd found the TARDIS…

And then Giles understood. He didn't need to get in to the TARDIS. What he needed was the Doctor.

* * *

><p>The blonde girl had introduced herself as Buffy. Buffy the Vampire Slayer. Rose had giggled, inwardly. The name didn't exactly strike fear into hearts, but she and the Doctor once met an enchanter called Tim who could blast through four-inch plasteel with the snap of his fingers.<p>

Now they gathered around the kitchen island, elbows deep in weaponry, while Buffy addressed them. "It's good to have another Watcher on board," she said. "With the Council destroyed, I was afraid we'd lost them all, and while they've not been overly with the helpful in the past, I think Giles will need all the support he can get…"

The Doctor minced among them, picking up every odd weapon, dish, and utensil, examining each book title and package label as he went.

"So," Buffy went on. "Any luck with the mask-y demons? Anything beyond 'they're re-enacting the robbery from _Point Break_?'"

Willow launched into a lengthy description of what the creatures were not, including adolescent turtle mutants and the creature from Predator. The others joined, each in their turn, except for Dawn, who slunk into the corner between the sink and the fridge and watched while trying – and failing – to look as though she didn't care.

The Doctor slipped up beside Rose and together they moved away from the group.

"So what've we got?" Rose whispered.

"Lots of power gathered in this room," he whispered back. "The ginger," he nodded to Willow, "She absolutely resonates. I'm guessing witch or high-level technopath. But her energy's off somehow, like something's distorting it. And that one," he nodded to Anya, "She's old. Way old. Older than me, and that's saying something."

"But she's human, yeah?" Rose asked.

"Vengeance demon – well, she was, now she's human – well, for now. And from what I gather, Miss Feisty–" he indicated Kennedy, "–Is a Potential Slayer. Same with all the sleeping girls, they're Potentials, too. See, the system works like this, in every generation one Slayer is called to fight the forces of evil, blah blah destiny, blah blah darkness—"

"—What, just one?" Rose interrupted.

"One what?"

"Slayer, of course."

"Ooh, right," he said. "Most cases, yeah."

"A bit dodgy, don't you fink? What if she dies?"

"_When_ she dies. Dangerous occupation, Slayer. So when the inevitable happens another is called to take her place. Any one of these has that potential."

"I get it. Potential Slayers." Rose thought for a moment, taking it all in. The Slayer and the others continued to discuss demons and vampires as if these things were all part of their regular routine. Then a thought occurred to her. "Doctor?" she asked.

"Yes, Rose."

"Do we have vampires and Slayers in our own world?"

"Yes, but not like this. Not on this scale," he said. "In our universe, Torchwood is essentially the alien encounters branch of the Watcher's Council, and both're part of UNIT. We have vampires, ghouls, mummies—"

"—Werewolves," she put in.

"Right you are, but here," he scanned the room again, examining the Slayer, the Potentials, the witch, the demon, and whatever Dawn was. "Here it's gone off somehow. It's gone wrong. Things that shouldn't be, are. Everything's out of balance."

"And that's never good," Rose said.

"No, it's not."

"So why is this lot all gathered here?" Rose asked.

"They're at war," the Doctor said. "And they're losing."

* * *

><p>Frak found himself shaking his head again at Frell's antics. They crept along the open sidewalk, sliding along hedgerows and ducking behind vehicles in pursuit of the elder human they followed out of the sewer. Frell had even persuaded Frak to deposit the slightly unconscious humankind they had lightbursted earlier so that they could follow with greater stealth and speed.<p>

"Are you certain, Frell?" Frak said once they came to a trash receptacle and watched the elder man slip across the street. "You know what Senator Frawlis always say: One ptarka is worth forty-six in the kinintzchel."

"I tell you true, Frak," Frell said. "He carries a fancy glowy thing that has the same pulse signature as the Source. He can lead us to it, of this I am sure."

"But we encountered the Source underground," Frak pointed out.

"Right you are, comrade, but we traced the Source through rift and veil before our terrible fall, so might we not conclude that it can move of its own accord?"

Frak vented his neck ducts. "Your logic is sound."

"Thank you, Good Friend."

"No, thank you. And even if we're wrong, we'll have a nice snack for later."

The elder man was moving again, making a dash up a shadowy sidewalk before cutting across an open lawn and sidling in between a pair of recycling bins.

"Follow at a goodly pace," Frell cautioned. "We cannot risk losing him in all this shadowy shrubbery."

"Indeed not," Frak whispered. "Lightbursters ready?"

Frell held up his laser wand. "Set to stun," he said. "For now."

With a nod, both aliens trundled across the street, following the same path as the elder man.

* * *

><p>The sound of Xander and Anya catapulting into a sudden and intense side argument about demons drew the Doctor and Rose back into the conversation.<p>

Andrew the Bite Wound muttered, "I'd ship that."

To which Anya growled, "Not without some legal recourse."

"Guys," Buffy said. "Let's just stay focused. Masked demons…"

And the discussion continued.

"She's a fine leader, that one," the Doctor said. "They'd follow her to the end of the world. And have, I'd wager."

"So what about the boys?" Rose asked. "Where do they fit in?"

"Tin dogs," the Doctor said. "Much like your boy Mickey."

"Stop…"

He grinned down at her a moment, then returned his gaze to Dawn. "But that leaves us with her. Where does she fit in?"

"She one of the Potentials? She i_is/i_ the Slayer's sister."

"No," he said. "She's something else. Something different…"

"So what do you think, Doctor?" Buffy asked.

The Doctor and Rose stood for a moment, mouths agape, seemingly caught off guard.

But the Doctor said, "I _think_ the creatures you mention – the mask-wearing demons – they're not really demons at all."

"But they're not vampires…" Xander said.

"No, they're not," the Doctor agreed. "They're aliens."

Silence spun out, perforated by Andrew, who said, "Like, outer space aliens?"

"Yes," the Doctor answered.

Andrew raised his eyes and whispered, "Beam me up. Please." Xander punched him in the shoulder.

"We have dealt with extra-terrestrials before," Buffy said.

"Have you now?" the Doctor asked.

"A few years ago," she said.

"That's right," Willow said. "The demon, Queller."

"Ah, the Demon Queller," the Doctor exclaimed. "Knew him well. Physician to the Chinese Emperor Kammu round about eighth century. Decent bloke, snazzy dresser, grievously misunderstood. He was posthumously appointed as the Emperors' protector, though, so it all worked out…" He trailed off when he noticed them all staring at him as if he had sprouted a prehensile tail from his forehead.

"He's kidding," Rose said. Through her teeth, she added, "Always kidding, right Doctor?"

"I love my brain," he said, tapping his forehead. "All these wild stories bouncing about."

"Typical," Kennedy said, slamming the table. "Watchers slaughtered the world over, and we get the Council crazy."

"He's not crazy," Rose said.

"Well he ain't sane. And he ain't helping."

"Kennedy, stop," Buffy said. The younger girl looked as though she might lunge for a crossbow, but managed with some effort to restrain her temper.

Buffy rubbed her eyes like a frustrated child, and it struck the Doctor how utterly exhausted she seemed. How often had he seen women like her – fighters and commanders who were young in years yet old at heart?

Countless times, throughout time and space, and it never got easier.

Buffy looked at him, looked as though she sensed what he was thinking. But after a long moment, she pulled her attention back to her group.

"Look, guys, we're all tired. I say we come at this after a few hours' rest."

"No arguments here, boss," Xander said.

Willow motioned to Rose and the Doctor. "C'mon, guys. Let's find you a matt or a towel to sleep on. There's an idea – bathtub!"

"Hang on a sec," Buffy said. "I'd like a word with the Doctor."

"Oh." Willow looked like a schoolgirl about to leave her best friend in the principal's office. She patted Rose's shoulder and whispered, "Good luck," as she and Kennedy squeezed from the room.

Everyone filed out of the kitchen, leaving Buffy alone with Dawn, Rose, and the Doctor.

Without even looking at her, Buffy said, "Dawnie, go on to bed."

"No, Buffy, you don't understand –" Dawn said.

"Please don't argue with me," Buffy said, her voice stretched thin like a tightened rubber band. "You went out again, on your own, with this place crawling with Bringers and demons and—"

"—Aliens," Rose said.

"Whatever," Buffy snapped. "You could've been killed."

"But I wasn't," Dawn said. "I _can_ take care of myself. Isn't that what you've been training me to do – take care of myself so I can stay out of your way?"

"What were you even doing out there?"

Dawn glanced at the Doctor, then looked down at her hands. "I don't know," she said, and they all saw through the lie.

"That's the big question, innit?" the Doctor said. "Perhaps _the _question. What was Dawn doing out with such dangers all about?"

"She dreamt about it."

This came from a new voice that took them by such surprise they all jumped, except for the Doctor, who merely gave the newcomer a good, long, incisive stare.

"Giles?" Buffy said.

"How did you know?" Dawn asked.

Giles stepped into kitchen. "I'm right, aren't I?"

"Doctor," Rose said. "He's the Krillita…"

The Doctor pressed his lips thin and gave a miniscule shake of his head.

"'nother Watcher," she finished. "I'm guessing."

The Doctor took a few steps toward Giles, studying him closely. "Yes, and we've met before, though you went by another name, in't that right?"

"You haven't aged a day, not a day in all these years," Giles said. His eyes took on a wide, staring expression, like something bordering hysterics. "It's unbelievable."

"And you're a Watcher now," the Doctor said. "No longer chasing after Eyghon, how grown up of you." The Doctor moved sideways a few more steps, and from the corner of her eye, Rose caught the twitch of his finger beckoning her to follow.

Buffy's brow furrowed. "He hasn't aged a day… is he a vampire?" She turned on Dawn. "Did you invite him in?"

"I didn't," Dawn cried. "Oh. Well. Kinda. But… it's not what you think."

"You know what I think?" Buffy said, hefting the halberd from the pile of weapons on the bar. "Somebody better get explain-y, before I get a little headbash-y."

"Buffy, wait—" Giles said.

The Doctor grabbed Rose's hand and pulled her into the dining room, only to be met on the other side of the table by a fiercely blond fellow in a black duster.

"Well, well," Blond Fellow said, "Trouble's afoot."

The Doctor looked him over. "Nice coat," he said. Then he sucked air over his teeth. "You've got something in your head. Did you know?"

Blond Fellow gripped the Doctor by the collar and wrenched him around to face Buffy, who swung the halberd blade at the Doctor's throat. Rose responded by groping blindly at the weapons on the table and coming up with a mini-crossbow, which she pointed it at Blond Fellow's head.

"Let him go!" Rose shouted.

The Doctor indicated with a meaningful head tilt that she should aim for the blond man's heart. "Right," Rose whispered, breathless, and brought the nose of the weapon to its new target.

"Spike, Buffy, stop it! Everybody just stop," Dawn said. She stepped between Buffy and the Doctor. "I can explain if…" Dawn darted a distracted glance at the dining room table. "Hold on, who found this?"

Dawn plucked the crinkled sheet of paper from the table.

"We found it at the site. Anya called it an astrological casting," Buffy said.

Both Rose and the Doctor could make out the intersecting patterns and swirls on the page. Rose had seen similar things on the readout screen of the TARDIS and in other far-flung places with space ports and way stations, and though she couldn't read them, she knew what they were.

One look at the Doctor confirmed Rose's suspicion, and he was on the verge of explaining when Dawn held the page between her hands and said, "I thought I lost it."

"L-lost it?" the Doctor said. He shrugged out of Spike's grip and stepped forward to examine the paper over Dawn's shoulder. "_You_ lost it? You _drew_ this?"

And then, quite unexpectedly, everything went white.

* * *

><p>The Doctor and Buffy awoke before the others, only to discover that they were arranged around a broad circular gangway of metal mesh about six meters wide, suspended five meters above a dubious looking oily black sludge and chained with their wrists looped over a metal guardrail.<p>

Something on a lower platform drew the Doctor's eye: a metal antenna of some sort, crafted from scavenged pieces of Earth technology and what appeared to be the communications hub of an exploration class space vessel from the Vriskain sector.

Directly across the gangway from the Doctor, Buffy began to thrash about to test the strength of the chains as soon as she was conscious.

"You needn't bother," the Doctor said. "They're xyraditan steel. Space faring weight, meant for hauling asteroids and cosmic slag."

Buffy continued to struggle. "Yeah, Doc? You're gonna want to get free, because we're in Sunnydale, right on top of a Hellmouth, and there are more than just demons down here. Dawn!"

To Buffy's right, Dawn winced in her sleep. The Blond Bloke – Spike – was to Buffy's right, and he was beginning to revive.

"A Hellmouth," the Doctor said, grinning. He nudged Rose with his shoulder. "Rose, did you hear that? They call the rift a Hellmouth. Get it? A mouth. To Hell."

Rose made a muffled, sleepy sound and slunk against him. Buffy managed to get to her knees, but the chains nipped into her skin like razorblades. Still, though she twisted and pulled and wrenched, the chains held.

"Here… if you'll just…" the Doctor got to his knees as well, gently sliding Rose to rest against a joist. He turned to his left to find Giles unconscious, his forehead to his wrists, and in his hand he gripped…

"Now what have we here?" the Doctor wondered aloud. He bowed his head to jostle Giles' shoulder. The older man's weight shifted and the green steriglass strip slipped from his hand and skittered across the mesh, where it glinted under the cold blue light… of what, exactly?

The Doctor lifted his head.

"Ah now, that's nice," he said, smiling. He nodded to Buffy. "You were right. Far more than demons down here."

Buffy glanced over her shoulder just as the enormous maw of the main hatch hissed open and the central walkway began to lower slowly down toward them.

"Mother… ship," Buffy said.

* * *

><p>Senator Frawlis swept from the main walkway in a flutter of black ploxy-satin. He approached the six captive humankind with all of the pomp and solemnity he could muster. He hoped that it masked his continued frustration at Frak and Frell, who not only failed to bring him a meal, but also insisted that they had found the Source.<p>

However, neither could actually identify the Source nor could they provide Frawlis with anything more concrete than, 'One of them had a fancy glowy thing.'

At least some of them looked plump enough to munch upon. He could see the thirty or so humankind slumped in the mouth of the tunnel that curved off the main chamber. Frell and Frak were scurrying along the slimy stone path, ready to deliver the official count for the evening's work. No doubt they would expect some kind of reward.

Senator Frawlis cringed inside his metal skin. This world didn't brook with slavekind. Here, work met with payment, usually in the form of monetary reward, which was then traded for various entertainments.

Frawlis timed his descent perfectly so that he stepped from the walkway the moment the lip connected with the platform. He stepped into the circle and let all those shackled within gaze up at him in terror and awe. As if on cue, Frak and Frell scuttled over the edge of the circle.

"Now," Frawlis rumbled, modulating his voice to its deepest and most magnificent setting. "Tell us where you have hidden… the Source!"

A long pause ensued, in which the humankind quaked and trembled and cried out to one another. And then, one of them – a narrow, stickish sort of man – began to applaud.

Moments before, when the alien leader began to descend toward them, the Doctor whispered to Giles, in hopes that he was awake enough to hear him, "In my pocket there's a device. Can you reach it?"

Rose's eyelashes fluttered open. The Doctor shook his head. "No, stay asleep. Pretend."

He felt a gentle nudge on his shoulder and craned around to see a glint of silver concealed in Giles' palm.

"Great work," the Doctor said, and he set about the surreptitious task of unbinding his wrists. He glanced at the warship again and said, "It's Vriskian Fellowkind, judging by the louvered gangplank and the crenellated metalwork. Oh, I like that." He said it again, enunciating each syllable.

"Doctor," Giles warned.

A pair of the Fellowkind approached from below and in tunnels nearby, the Doctor could hear dozens more, all of them industriously hauling and scraping. But hauling and scraping what?

"The Fellowkind aren't warriors, they aren't hostile. They're a strictly spacefaring race," he said. "They travel from place to place, trading whatever they can and stealing if they can't."

"So basically they're… pirates," Buffy said.

"Precisely. But this is different. They must have been pulled off course. If I could talk to them…"

"Talk to them?" Buffy said. "They kidnapped us, put us in chains, and there's a pile of half-conscious people in a sewer tunnel right over there. In my world, that counts as hostile."

"Buffy," Dawn said. "I think we can trust him."

"Best you stay out of this, Niblet," Spike said.

"What? Why?" Dawn was incredulous. "Because I'm young? Because I'm just human?"

"Because we don't know who he is, beyond some dubious connection to Giles during his Ripper days," Spike said.

"And he lied to us about being a Watcher," Buffy finished.

"See, that's where you're wrong," the Doctor said. He continued to work on the xyradite chains, but they proved to be quite a challenge for the sonic screwdriver. "I watch. And sometimes, I intervene."

The chain broke just as the Vriskian Senator stepped from the gangway. Quickly, the Doctor tucked the sonic screwdriver into Rose's sleeve.

"Now," the Senator growled. "Tell us where you have hidden… the Source."

"Bravo!" the Doctor said, clapping his hands. "I mean, that was beautiful. That was… well done. And your ship, it's just marvelous. Is that tempered feldspeen stelliglass? Absolutely stunning."

"Why… yes, it is," Senator Frawlis said, genuinely taken aback. "So few non-Fellowkind appreciate solid Vriskian workmanship."

"Vriskian Fellowkind, how 'bout that?" the Doctor said. "My, you are a long way from home. So tell me, Senator—"

"—Frawlis."

"Senator Frawlis, what is this Source you keep yammering about?"

"We need it to return home," Frawlis said. "Our receptor tracked its signal here —" he gestured at the makeshift antenna on the other side of the platform, "— but only tonight, the signal vanished."

"What, just like that?"

One of the masked minions flanking the Senator leaned in and said, "Oh Great and Conscientious One. Might we remind you that this prisoner has somehow managed to escape his chains, Sir?"

The Senator hissed through his nose vent. "Yes, Frell. I am aware."

"Well," the Doctor said. "That receptor is an ingenious device. Quite resourceful, how you pieced it together. But I have to ask, why is it you need that slapdash pile of humans over there?"

From behind the Senator came a tink of breaking metal. The three Fellowkind turned to see Buffy crouched before them, her bloody fists raised to strike.

"Excuse me, Doctor, but are you gonna flatter them to death?"

"No, don't!" the Doctor shouted, but not soon enough, for the Slayer had already launched her attack.

* * *

><p>"Rose!" the Doctor cried. "Setting 658D, hurry!"<p>

She twisted the sonic screwdriver and set to work on her chains. In moments, she broke free and went immediately to help Giles. Meanwhile, one of the minions intercepted Buffy mid-leap, and the pair of them fell in a tangle on the metal catwalk. The other lunged for the Doctor, who dropped to one knee and caught the sonic screwdriver just as Rose tossed it his way. The Doctor rolled forward and came up beside Dawn.

Straight away he went to work on her chains, but they were delayed when a metal arm panel clanged off the guardrail inches from Dawn's face. The Doctor turned to see the minion – his mask torn and greasy – retreat toward the gangplank and examine his damaged arm. Then, his body stiffened, his head rolled back, and his mouth cranked open wide.

"Cover your ears," the Doctor shouted, clamping his own hands over Dawn's. Rose, Giles, and Buffy managed, but Spike and the Doctor writhed in agony as the minion released a screech like that of a thousand million rusty hinges opening at once.

Silence followed, as even the Fellowkind seemed stupefied by the brilliant outburst of sound. Rose stumbled forward and pulled the Doctor against her body. His eyes bulged, his mouth hung agape, and the muscles in his arms and legs bunched and cramped. Beside him, Spike suffered the same crippling affliction.

"Doctor?" Rose said. "Doctor, can you hear me? Are you all right?"

He nodded weakly and turned within her arms to see the three Fellowkind gathered at the end of the gangplank. Below and beyond, they could hear the rhythmic tinkle and scrape of metal feet marching toward them.

"W-what did they do?" Dawn whispered.

"They called for back up," Rose answered.

The Doctor shook his head and sat up, and though he still looked dazed, he said, "Senator Frawlis, this can end now. Let the humans go, and I swear, I'll help you."

The noise of the Fellowkind filled the cavernous corridor. The Senator rattled his talons together and his mouthpiece curved into an unmistakable sneer as his army surged forward through the sludge and formed a circle around the base of the platform.

"We have no desire for your assistance, Doctor," Senator Frawlis said. "All we need is the Source."

"Right. The Source," the Doctor said. "Off we go then." Ignoring the Senator, he lifted the sonic screwdriver to Dawn's chains and sent the pulse through the xyradite.

"See, your Great Munificence," Frell cried. "He has the fancy glowy thing. He can find it. He can trace it."

"Yes, yes. Frak, collect him and put the others with the stores…" Frawlis said.

"Oh, and Rose," the Doctor interrupted, off-handedly, as he continued to work on Dawn's chains.

"Yes, Doctor?"

He glanced over his shoulder and gave her his most serious stare. "Get them out of here. All of them."

That was when all chaos broke out.

* * *

><p>Spike, still chained, kicked the first two Fellowkind soldiers over the guardrail. Once he and Dawn were free, Spike had round-housed another over the edge, where it landed in the sludge with a satisfying crunch, but then crawled out again, none the slower.<p>

"They're like machines," Spike hissed.

"They _are_ machines," the Doctor said. He and Dawn ducked another round of attackers, but once again Spike defended them. He was nimble and strong, much more than a mere human, and suddenly the Doctor understood.

"You're a vampire," the Doctor said.

"Worked that out, didja?" Spike quipped. Another Fellowkind leapt in; Spike dispatched him over the rail.

"But he's a good kind," Dawn said. "He has a soul."

The Doctor laughed. "This world gets all the weirder. It's all so… sort of… thin and threadbare. Too much winter, not enough jumper. And you," he said to Dawn. "Where do you fit in?"

"Me?" Dawn balked.

"Yes. You." The Doctor stood up amidst the fighting, held up the sonic screwdriver, and set it to scan the vicinity. He caught a corresponding flash of green light from across the platform. The steriglass!

The Doctor darted across the platform and arrived at the glass wafer just as Giles closed his hand around it.

"You can stop this," Giles said, and his voice quavered. "You can stop all of it, can't you?"

"Where did you find this?" the Doctor shouted.

Giles cupped the glimmering wafer in his hands and stared down into it. All around them, the sounds of fighting dulled to whispers and the lightbursts of the Fellowkind's weapons faded to flickers. Somewhere far below, Buffy and Rose had made it to the prisoners, and Giles could hear the girls shouting. It fell to echoes and heartbeats.

"It doesn't matter," Giles said. "You have the power to close the rift. You can seal the Hellmouth forever. You can save us all."

The Doctor considered a moment. He shot a quick look at Dawn. "No," the Doctor said. "I can't."

"You can't or you won't?" Giles shouted.

"I'm not part of your universe. We were pulled here through the void," the Doctor said. "Wait. The void. The Source." He began to pace. "Alike but not alike. Old but not old. Yes. Yes. The walls are thin. They must have gotten pulled off course somehow, tumbled in by mistake and the crossing burned up their energy cells. They need a power source to get back out. But they'd need a generator the size of an AT-AT to pull it off. Unless…"

"The TARDIS," Giles said.

"Yes. Yes! Look at you. Brilliant."

Giles grinned, sheepish.

"They locked onto us by mistake, yanking us through the void, which brings us to this…" The Doctor snatched the wafer from Giles' hands, moved backward several steps and held up the wafer. "This is a device on a string."

"Like a yoyo?" Dawn asked.

"What up," the Doctor said, grinning. He pressed the sonic screwdriver to the wafer, which ignited in a fountain of sparks. In seconds, the TARDIS began to materialize on the platform. In one swift motion, the Doctor hauled Dawn to his side and the sewer tunnel disappeared.

* * *

><p>"Can you make this jump?" Buffy called to Rose.<p>

It was a long way down, but the pit below was filled with oily goop, so she could probably manage. Behind them, Spike was busy lobbing Fellowkind off the platform.

Rose gritted her teeth. "I must tell the Doctor to have stern words with our cruise director."

"Can you make it?" Buffy snapped.

"A'right!" They climbed over the guardrail. Rose dangled for a second and then dropped. She landed with an unpleasant squelch and pitched her weight forward to roll onto the slippery stone walk.

"Not bad," Buffy said. She'd made a much cleaner landing, in every sense of the word, and bent to help Rose to her feet.

The lower level was aclatter with the Fellowkind trying to coral the humans who had begun to wake the moment the minion issued his shriek of attack. A few Fellowkind broke off from the group and bounded toward Rose and Buffy, their lightburst guns raised.

"Don't look at it!" Rose shouted.

They averted their eyes in time for the first flash, but soon the ones climbing from the sludge were on them as well, and both girls shot off at a run toward the prisoners.

By that time, the humans were awake and screaming. The Fellowkind scrambled around, lightbursting frantically, but the flashes created a dizzying strobe effect in the close darkness of the tunnels. Buffy and Rose drew up short of the confusion and watched, dumbfounded, as the Fellowkind tried and failed to herd the human prisoners.

"The Doctor was right," Buffy said. "These guys: definitely not warriors."

"Still, they're trafficking human," Rose said.

"That's where we come in," Buffy said.

"Got a plan?"

"Always."

Buffy climbed up the slick ledge of a sewer tunnel and scissor-kicked one of the Fellowkind from behind, sending him like a domino into three others. They tumbled into a useless heap while Rose moved in to help the people cowering against the tunnel wall.

The trouble was, now that these were free, Rose didn't know what to do with them. Flashing bursts down the nearest tunnel meant more fighting. The other tunnels were so dark, she had no idea how she could lead them to safety without getting hopelessly and dangerously lost.

But there was another option. Buffy continued to kick robot ass, but there were twenty Fellowkind and only one of her. And since the Fellowkind didn't seem to want to kill the humans, there could be little danger in...

Rose crouched among the wide-eyed prisoners. "Hi. I'm Rose. And I know this all has to be nightmarish, but you'll get out of it alive. All of you. But right now, you're gonna have to fight."

Buffy slammed one of the Fellowkind into the ground and it slid to their feet, its latex mask askew on its glinting silver face.

One of the men stammered, "They're… aliens."

"That's right, they are," Rose said. She bent and ripped the mask from the Fellowkind's face. "And if you wanna get out of here," she said, crumpling the mask in her fist. "Fight back!"

The man's eyes widened. His teeth clenched. "Right," he shouted, surging to his feet. One of the Fellowkind nearby lightbursted him, and he fell backward into the group.

"Yeah, you'll want to avoid that…" Rose said.

A woman in a nightgown and curlers sprung up then and growled, "Let's get 'em!" The others followed her lead, and soon Buffy was no longer fighting alone.

Rose had just joined the fray when she heard a familiar sound behind her. She turned, amazed, to see the TARDIS appearing on the platform. As it solidified around him, the Doctor whipped forward and pulled Dawn inside.

Everyone – Fellowkind and humankind alike – stopped to stare at the TARDIS. The humans huddled together and the Fellowkind turned in unison to face Senator Frawlis.

Buffy staggered to a halt beside Rose. "What has he done?" she cried.

"I don't know," Rose said.

"He's got my sister inside that—" Buffy's face clouded. "—A police box? What does that even do?"

"It's the TARDIS," Rose said.

"Yeah, that's so much better."

"Listen, you have to trust him…" Rose said. "He knows what he's doing. He won't hurt her, and he'd never leave us behind."

Just then, the engines swelled to life and the TARDIS dissolved away.

* * *

><p>The TARDIS was dark and silent inside.<p>

Dawn said, "What's happened? Why are we in here?"

The Doctor responded from somewhere well away from her. "There might be enough power for one trip, if we hurry."

"We can't leave them," Dawn said.

"Oh we won't, Dawnie Dear. We'll be back before you can say Raxocoricofallapatorius. But first—"

There was a sound of a lever clicking. The emergency lights flickered and the Doctor appeared, looming over Dawn, the planes of his face painted an ominous orange and green in the half light.

Dawn recoiled. "But your ship. It's without power…"

"Yes, it was."

"And now it's not?" she ventured.

"Now it's not." The Doctor's eyes twinkled. "Don't you see?"

"No?"

"You're the piece that doesn't fit. Old, but not old. Alike, but not alike." The Doctor ripped the bandage from her arm and she winced. "Sorry."

One drop of her blood welled from the wound. He turned her arm and let it fall into the heart of the TARDIS. Instantly, a spark bloomed within it, a tiny rosette of golden flame. It caught light and feathered along the hexagonal matrices, the spaces between filling up with rippling incandescence.

"Is that… from me?" she asked.

They stared a moment more, transfixed, before the Doctor lowered the panel. All around them, the TARDIS systems were waking up, blinking into life.

"But how?" she said. "I don't understand."

"No, you don't," the Doctor said. "And I'm so sorry. They never even asked, did they? Never even gave you a choice."

"Who?"

"I think you know. At least part of it…"

Dawn suddenly remembered the scrap of paper in her pocket. She pulled it out and smoothed it straight between her hands. "This," she said. "What is this?"

The Doctor's lips quirked into a half-smile. "That would be Minkowski Two Dash Nine, otherwise known as the Butterfly Nebula, located two-thousand light years away. You've drawn a star chart."

Dawn's knees buckled and she sat down hard on the metal floor. "I was talking on the phone with Kit and doodling in my journal. And then, I dreamed... Later that night, I dreamed about a place…"

The Doctor cranked the hand brake. "You wanna see it?"

"You can do that?" Dawn asked.

"I am _very_ good," he said.

The Doctor read the choice in her expression. He dialed in the coordinates with the NAGCS crystal and dropped the brake. A heartbeat later, they were hurtling into space.

* * *

><p>"You were saying?" Buffy said as they watched the TARDIS disappear.<p>

"No. He has a plan. He—" Rose said, but Buffy was already charging forward, back to the platform and Senator Frawlis.

"Spike!" Buffy called up. "Take out the leader!"

"I'm trying," Spike said through his teeth. He grappled with the main two minions, who seemed determined to keep him away from the Senator. Meanwhile, Frawlis himself was shouting commands to the underlings below, trying and failing to get them organized enough to re-capture the human prisoners.

Several of the Fellowkind tried to block Buffy as she ran toward the ship, but she used them as stair-steps to vault onto the gangplank.

Frawlis brandished his lightburst ray. Buffy kicked high and sent it flying.

"Our s-ship is not operational," the Senator said.

"Not my problem," Buffy said.

She took another step forward. The Senator retreated toward the ship.

"Call them off," she said.

"We need the Source," he said.

"I said, call them off!"

The Senator cranked his head backward and unhinged his jaw so that his mouth fell open wide.

"Oh no you don't," Buffy said. And with a well-placed kick, she knocked the Senator's head from his shoulders.

It rattled across the gangplank and fell with a clattering crash to the sludge below.

Frell whirled on Buffy and wailed, "Our Beneficent Master! You have doomed us! You have doomed us all."

"But I was – He was – You were – I tried to tell him."

"Kill them!" Frell screamed. "Kill them all!"

* * *

><p>Dawn and the Doctor stood in the open door of the TARDIS, staring out into the luminous veils of the Butterfly Nebula. Blown by unseen radiation currents, the dusts and mists wafted and sparkled amongst the stars like curtains teased by ghostly fingers.<p>

After a long unbroken silence, the Doctor said, "This is it. The place of your birth."

"It's so peaceful," she said. "So calm."

"There you were, happy glowy particles of light drifting among the stars. They took you, gave you form, gave you _this_ form. Made you The Key."

A tear rolled down Dawn's cheek, glinting in the green light.

"It was your blood that opened the TARDIS," the Doctor said. "Your blood that awakened her. With your blood, you open rifts between worlds, and that makes you dangerous. The most dangerous girl in the world."

"I-I'm not dangerous. I'm just regular-ordinary-klutzy-bothersome-kid-sister me."

"Those are things you will never be." His frown deepened. "I don't figure the men who created gave much thought to how long you'd last, or what would happen to you if you got used up – or didn't. You had never known pain or grief or loneliness before, all those human concepts, and they never even asked if you wanted it. And I'm so sorry. So very sorry."

Dawn wiped her eyes. "Do I have to die?"

The Doctor flinched as if she'd slapped him. "No," he said, taken aback by her willingness to accept her death, as if she'd always expected it. He pulled her into a hug and kissed the top of her head. "How can they not hear you?" he asked. "You're so alone, you're screaming."

* * *

><p>He let her cry. No one ever let her do that. Just cry. Dawn loved him for that.<p>

* * *

><p>"Now," he said, after a time. "Which place is home? Do you stay here, or return, with me?"<p>

Dawn considered a long moment before speaking. "Will Buffy miss me?" she asked.

"I can make it so she forgets. You're not meant to be there anyway. You'll lift out like you never were. History will re-write itself, and you'll be like a dream half-remembered at waking."

Dawn stared out at the glimmering gauzy sheers of dust. She felt it, calling to her. It was the stuff that made her, her first mother, her family, and it sang to her at night in her sleep. It was her half-waking dream. She wondered if she once missed this place, the way she missed Buffy when she died.

A thought occurred to Dawn then. She said, "When I die, will I return here?"

"Now that I don't know," the Doctor said, once again of the pensive brow. "Could be you'll die a human death and go wherever it is they go. Or you could wind up here. Either way, you'll have to choose now and hope for the best."

Dawn closed her eyes. "Fair enough," she said. "I know what I have to do."

* * *

><p>The TARDIS began to return just as Giles was running forward to stop Buffy, but he was too late. Buffy kicked the Senator's head from his shoulders; Giles ran into the very solid outer wall of the TARDIS.<p>

The Doctor and Dawn stepped out into chaos, with Frell now shouting commands and Spike and Buffy down in the thick of the fight. The Doctor couldn't see Rose anywhere. He did see a number of the human prisoners lying face down in the sludge, and noticed that the Fellowkind's lightbursts had changed in color. They had been white-blue; now they were fiery red.

Which could only mean…

There it was, still lodged in the mud – Senator Frawlis' metal head.

"No! What have you done?" the Doctor shouted. He slid down the outer gangplank, his coat flying out behind him. He dashed across the distance, dodging lightburst bolts as he ran, grateful that the Fellowkind had terrible aim.

The Doctor slid to a halt and hefted Senator Frawlis' head from the muck. He performed a scan and found that the connections were severed but the neural matrices were very much alive. After a quick adjustment to the screwdriver's settings, plus one very close shot by a Fellowkind bolt that left the Doctor's sleeve sizzling, he was able to find the circuit switch.

One properly placed pulse later and the Senator's eye slots shot open. He opened his mouth vent to speak, but the Doctor spoke first.

"I've found the Source and I can help you but you have to call off your Kind," he said.

Frawlis' head made a series of rattling clacks. His mouth moved sluggishly, and when he spoke, his voice came out muffled and thick.

"She…booted…me…in…the…head."

"And she promises never to do it again," the Doctor said. "Please—"

"Doctor!" It was Rose. He whipped around to see her cornered against a massive metal grate with the remaining human prisoners. The Fellowkind had them trapped, and though Buffy and Spike were battling their way through them, there wouldn't be enough time.

The Doctor held the head of Senator Frawlis high above his own head. "You see that girl up there, that small human girl. _She's_ the Source. One drop of her blood can send you all home. The little side trip I took just proved it. Tell them."

The Senator made a noise that sounded very much like the drawing of breath, and then he said, "My Fellowkind, desist!"

The word echoed and hissed and bounced through the chamber. All at once, the Fellowkind lowered their weapons and turned to behold their master. When they saw that he was still alive, every Fellowkind fell to their metal knees and bowed their heads to the ground.

Frell warbled, "Alive! Our master is alive! All hail Senator Frawlis, Who Excels at All Things, Including Death."

"All hail!" The Fellowkind snapped and then returned to attention.

Rose joined Buffy and Spike and together they crossed the chamber to meet up with the Doctor.

"Now, we haven't much time," the Doctor whispered. He cradled the Senator's head in the bend of his arm. "We have to reconnect his head or his power cells will drain completely. Rose, we're gonna need the medical kit from the TARDIS, oh, and Frawlis…"

"Yes?" the Senator groaned.

"You've killed people. Innocent men and women."

"They killed me first," he whimpered.

"Not this lot," the Doctor said. "You gathered these for a purpose, but there were others before, am I right?"

By now, Frak and Frell had dragged the Senator's body to the group, and Frak propped it against his own while Frell helped the Doctor to situate the head.

Frell said, "We didn't want to make the return trip without provisions."

"You mean they're nibbles?" Rose asked.

Frell rubbed his metal talons together. "Believe me, you taste delicious. Little sauce on the side…"

"Ew," Buffy said.

Spike merely shrugged, and she knuckled him in the shoulder.

"Also, you are so many," Frak said. "We didn't think you'd miss the few we took."

"Regardless," The Doctor said. "It's illegal to consume sentient life on any planet. You'll stand trial for your actions, and since you have no home world, you'll have to face the Intergalactic Spacefaring Council."

Senator Frawlis vented his nose duct and rolled his eyes in their sockets to fix them on Frak and Frell. "Oh, my faithful minions. You were acting on my orders, which you followed without wavering. I shall submit myself to the Council for these deeds and pray for their leniency. In the meantime…"

The Doctor reconnected the final wire in Frawlis' neck and the robot's arm swung out to grasp Frell's shoulder.

"…I transfer command to you, Frell, my able-minded comrade," Frawlis finished.

A cheer went up among the Fellowkind as Senator Frawlis got to his footpads and raised his arms in triumph.

"Now," the Doctor said to Rose. "I need to have a word with the Watcher."

* * *

><p>While Rose and Dawn tended to the wounded, Spike and Buffy helped to get the up-and-about ones up and out of the sewer. The Fellowkind retreated to the interior of their ship, where they awaited further orders from Frell the Able-Minded.<p>

The Doctor stood with Giles outside the doors of the TARDIS.

"There was another Doctor," Giles said. "A demon who worked in secret for the hell god, Glorificus. He read from a book called the Tarnis…"

"The _Tarnis_?"

Giles grinned wanly. "Yes." He took off his glasses and began to polish the lenses. "He was the one who… cut Dawn, who drew her blood to open the gateway between this world and all others."

The Doctor stared down at Dawn and Rose who were having a laugh with an injured woman. How strange they were, humans, to smile in the face of such pain and tragedy.

"_Begun by blood, by blood undone_," the Doctor said.

"You're not supposed to be here," Giles said.

"No, and neither are they," the Doctor said, nodding at the Fellowkind vessel. "Thing is, your world's not right. Sometimes dimensions have reflections of other realms in them. They're like ripples. Certain things get mirrored from one dimension to the next, though they're distorted, imperfect. That's the natural order of dimensional existence."

"Yes I'm familiar with Quantum String Theory."

"Then let's keep with your strings metaphor," the Doctor said. "We're not from the same world, you and me. Not even the same universe, yet Rose and I, and the Fellowkind, we were ripped from our dimension and into this one because the barriers here are thin. People here have access to technology they can't even begin to understand. It's like handing a nuclear missile to a ten-year-old. You've ripped so many holes in the fabric of your reality, it's falling apart. Can't you feel it? No, of course you can't feel it, you've grown used to it, but it's threadbare. Someday someone will come along and tug the wrong string and the whole thing will unravel around you."

"But you can close the rifts and seal off the Hellmouth. You can save us all."

The Doctor shook his head. "There are forces at work here, forces unleashed that have to be dealt with, and not by me."

"The First," Giles said.

"The First of many. There will be others. Things you can't even imagine."

Giles adjusted his glasses. "I'm a Watcher. I can imagine quite a lot."

The Doctor turned to Giles. "Someone will need to rebuild the Council and warn Torchwood not to tamper with other dimensions. They won't listen, they never do, but you can keep them in check."

At that moment, Buffy and Spike returned, and the Doctor noticed a tightening around Giles' eyes as he watched them cross the chamber to join Rose and Dawn.

The Doctor said, "She'll see you through, in the end. But you have to trust her."

"I always do," Giles said, but his hands gripped the guardrail so tightly his knuckles turned white.

The Doctor understood. It wasn't the Slayer that Giles mistrusted. It was the vampire. Like so many things in this dimension and in others, the Doctor would have to let that situation sort itself out.

* * *

><p>The Doctor made one hyper-quick side trip in the TARDIS to the Intergalactic Spacefaring Council, where he delivered Senator Frawlis to the high court to be tried for his crimes against humanity. He did speak on the Senator's behalf, though, saying that Frawlis had come of his own volition and submitted himself to the Council willingly. The Doctor counseled in favor of leniency, and hoped, from the bottom of both hearts, that the Senator received it.<p>

With the Fellowkind sorted and returned to their proper dimension, only one thing remained, and that was their own trip home. The Doctor assured Giles that he would seal up the particular rift through which the TARDIS had fallen. The rest would be up to the Watcher, in due course.

* * *

><p>Dawn stood shoulder to shoulder between Rose and the Doctor. They stared down in to the darkened control deck of the TARDIS.<p>

"Watch this," the Doctor told Rose.

Dawn pricked the tip of her finger and squeezed one drop of blood into the energy matrix. As it had done before, an ember of gold blossomed and spread throughout the hexagonal cells.

Rose gushed, "Wow, that's—"

"—Like Magic," Dawn said.

"Just like," the Doctor said. He closed the panel as all around them the TARDIS systems came online. He reclined against the deck and folded his arms.

"There ya go," Dawn said. "One drop of my blood. Kinda gross."

"And this is for you," the Doctor said. He held out his closed fist and when she cupped her hands beneath it, he dropped a single glittering spark into her palm.

"What is it?" Dawn whispered, reverent.

"Cosmic dust," the Doctor said.

Rose groaned. "You lot need lessons in the giving of gifts."

Both Dawn and the Doctor smiled.

"When we leave, it will cause a temporal shift," the Doctor said. "One side affect is amnesia. Everyone who was here will forget what happened. They'll think of it as—"

"—A waking dream," Dawn said.

"Yes. They'll recall vague impressions and suggestions, but they won't remember where the ideas came from," he said.

"But," Dawn said. "Please. I don't want to forget."

The Doctor grimaced. "The brain is a delicate thing. It forgets in order to protect. I can't save all of your memories, and some of them are best lost. But you will remember what you saw. With this."

The spark flared brighter for one brief second, and then melted into Dawn's skin. For a moment every cell in Dawn's body lit up, just as the core of the TARDIS had. To Rose, it was like sunrays illuminating clouds. To the Doctor, it was the wind rippling the silver leaves of Gallifrey.

And then she was Dawn again. Normal, ordinary Dawn.

"Thank you," Dawn said. She drew a steadying breath and left the TARDIS.

The Doctor watched the door a moment more before snapping into action. He spun the NAGCS crystal, dropped one lever, cranked another. He rounded the console and reset the monitor's coordinates for the new flight path.

"So where to next?" he asked.

"Where were we headed before?"

"No idea," he said and they smiled.

Then Rose's features darkened. "Will they be all right?" Rose asked. "The Slayer and her friends?"

"Oh, I dunno," he said with a sigh. "Much as anyone, I suppose."

Rose nodded. "Fancy a trip back home?"

"Yeah," the Doctor said. He released the hand brake and the TARDIS whirred to life.

Rose came around to join him. Together they toggled the final shift and soon they were speeding off, back to their own time and space.

They sat together in the flight deck chair, nestled close and comfortably silent save for the constant undulating hum of the TARDIS.

"Back in our world, do you fink…" Rose began. "Nah…"

"What?" the Doctor said, jostling her.

She jostled him back. "Do you fink I'd make a good Slayer?"

"Oh yes," the Doctor said. "Absolutely."


End file.
